Weigela is a genus of between 6 and 38 species of deciduous shrubs placed in the family Diervillaceae (formerly treated as part of Caprifoliaceae), within the order Dipsacales. All species are native to eastern Asia. Plants grow 1–5 metres tall and bear opposite, ovate-oblong leaves 5–15 cm long with acuminate tips and serrated margins. The showy tubular flowers are 2–4 cm long, with a five-lobed corolla in shades of white, pink, or red — rarely yellow — and are borne in small corymbs in early summer. The fruit is a dry capsule containing numerous small winged seeds.
The genus is closely related to Diervilla and has long been popular in temperate gardens. The first species to reach Western horticulture, Weigela florida (native to North China, Korea, and Manchuria), was introduced to England by plant collector Robert Fortune in 1845. After Japan opened to Western visitors, additional species were discovered by European plant-hunters in the 1850s and 1860s, though they were already familiar in Japanese gardens. Today, wild species have largely been replaced in cultivation by hybrid selections, most derived from crosses between W. florida and other east Asian species.
Etymology
The genus name Weigela honours the German scientist and botanist Christian Ehrenfried Weigel (1748–1831).
Distribution
All species in the genus are native to eastern Asia, with individual species ranging across China, Korea, Japan, and Manchuria. Weigela florida, the most widely cultivated species, is distributed across North China, Korea, and Manchuria.
Ecology
Weigela species serve as larval food plants for certain Lepidoptera, including the brown-tail moth (Euproctis chrysorrhoea). The flowers attract pollinators including bees and, in cultivation, hummingbirds.
Cultivation
Several Weigela species were prized as ornamental shrubs from the mid-19th century onward, but wild species have been largely superseded in cultivation by hybrids, primarily crosses between W. florida and other east Asian species. Modern cultivars offer a wide range of flower colours and foliage types. The following cultivars hold the Royal Horticultural Society's Award of Garden Merit: 'Red Prince', W. florida 'Alexandra', 'Florida Variegata', and 'Praecox Variegata'. Plants are generally easy to grow and maintain in temperate gardens.
History
Weigela florida was the first species collected for Western gardens, brought to England by Robert Fortune in 1845 from North China, Korea, and Manchuria. Following the opening of Japan to Western travellers, European plant-hunters discovered several further Weigela species and garden forms in Japan during the 1850s and 1860s, although they had long been cultivated in Japan. The British national collection of Weigela is held at Sheffield Botanical Gardens, alongside the national collection of the related genus Diervilla; Germany's national collection, the Sichtungsgarten Weigela, is located in Buckow, Märkische Schweiz.
Taxonomy Notes
Weigela has historically been placed in the family Caprifoliaceae, but more recent classifications (including the GBIF backbone and APG treatments) segregate it into the smaller family Diervillaceae, which also contains the closely related genus Diervilla. The genus sits in the order Dipsacales. The number of accepted species is disputed across sources, with estimates ranging from 6 to 38.
